Spray gun



1952 w. P. DAHRYMPLE 2,621,970

SPRAY QUN mad Juno 2. 1950 5 Sheets-Sheet 1 F I6. I

lmm 3 INVENTOR. WILLIAM P. DALRYMPLE ATTORNEYS Dec. 16, 1952 w. P.DALRYMPLE 2,621,970

SPRAY sun Filed. Jun. 2, 1950 5 Sheets-Sheet 2 al nz TzTi FTo 43H|4 FIG.4

62 6/ 50 a2 m B! 00/ INVENTOR. WILLIAM P. DALRYMPLE ATTORNEYS Dec. 16,1952 w. P. DALRYMPLE 2,621,970

SPRAY GUN Filed Juno 2 1950 5 Sheets-Sheet 3 J u 8 M. w WI w m m M m b mw w w @J H #l w 4101M a K. 1 a 6 5 W 4 I 7 W 5 f, Y. m q 2 M M a 21%:EM2... W/ W 44% H w m 1575. A ....VME=..... m

ATTORNEYS Dec. 16, 1952 W. P. DALRYMPLE SPRAY GUN Filed Jun. 2, 1950fgws 5 Shasta-Sheet 4 am a K28 H 2 55 M FIG.II

INVENTOR. WILLIAM F. DALRYMPLE WM) M ATTORNEYS Dec. 16, 1952 w. P.DALRYMPLE SPRAY GUN 5 Sheets-Sheet 5 Filed Juno 2. 1950 INVENTOR.WILLIAM F. DALRYMPLE ATTO RNEYS Patented Dec. 16, 1952 SPRAY GUN WilliamP. Dalrymple, Rochester, N. Y., assignor to American Brake Shoe Company,Wilmington, DcL, a corporation of Delaware Application June 2, 1950,Serial No. 165,786

12 Claims.

This invention relates to spray guns of the type utilized for sprayingsurface coating materials.

In the paint spraying field, there has been recently developed a methodof spraying paints, lacquers, and like surface coating materials throughthe use of steam as the pressure or motive fluid for atomizing anddistributing the coating material, and it has been determined that inmany situations such steam spraying of the coating material enables suchcoating material to be more economically and advantageously applied thanwhere pressure air is used as the motive fluid. In attempts to applythis process commercially, it has been found, however, that use of steamas the motive fluid introduces many problems, particularly by reason ofthe extreme heat that is encountered. Thus, it is found that in order toenable the coating material to be sprayed through the use of steam wherethe spray gun is to be handled by the workman, as distinguished frominstallations where the spray gun is permanently mounted as a part of amachine, there is an objectionable tendency to raise the temperature ofthe gun to such a point that it is extremely difficult for a workman tohandle and manipulate. Most spray guns heretofore developed for thispurpose have been of such a character as to require that the workmanprotect his hands through the use of gloves, and this is recognized asbeing undesirable because of the delicate character of the controloperations that must be performed in order to attain a proper and evendistribution of the surface coating material.

In View of the foregoing, it is the primary object of the presentinvention to enable spray guns to be constructed for use in a steamspraying operation in such a manner that the guns may readily be handledand manipulated by a workman, and an object related to the foregoing isto enable such spray guns to be so constructed that despite theapplication of steam to certain parts of the gun, the handle and controlelements thereof remain at a relatively low and unobjectionabletemperature.

Where steam is used as the motive fluid in the application or sprayingof surface coating materials, it is, of course, necessary to conduct thesteam to the spray gun through hoses or the like that are relativelystrong and heavy, and which in many instances may be insulated to avoidheat losses, and where such weight is added to the weight of the paintor coating supply hose, it is found that there is a tendency to disturbthe balance of the spray gun, thus to induce fatigue on the part of theworkman. It is, therefore, another important object of the presentinvention to enable steam spray guns to be effectually balanced inrespect to the steam and coating material supply hoses, and to therebyavoid undue fatigue on the part of the user of such guns.

It is recognized that one of the primary virtues of the steam sprayapplication of surface coating materials is the ability under suchproccesses to utilize relatively thick or viscous coating materials,thus eliminating the need for and cost of the usual solvents that arerequired in connection with spraying of surface coating materials. Asheretofore practiced, this surface coating material has been heated bythe steam as the steam strikes the surface coating material in themixing chamber or mixing zone of the spray nozzle, and this contact, ofcourse, takes place almost at the instant when the steam and theatomized paint or surface coating material are discharged from the spraynozzle. This has been found to be satisfactory in many instances, but itis a further and important object of the present invention to improvethe steam spray action through a more efficient application of the heatof the steam to the surface coating material. Another and related objectof the invention is to enable the surface coating material to be ineffect preheated by the steam as the surface coating material approachesthe mixing or atomizing chamber of the spray nozzle, and it is also anobject to enable this to be accomplished in a simple and expeditiousmanner.

Other and further objects of the present invention will be apparent fromthe following description and claims and are illustrated in theaccompanying drawings which, by way of illustration, show a preferredembodiment of the present invention and the principle thereof and what Inow consider to be the best mode in which I have contemplated applyingthat principle. Other embodiments of the invention embodying the same orequivalent principle may be used and structural changes may be made asdesired by those skilled in the art without departing from the presentinvention and the purview of the appended claims.

In the drawings:

Fig. 1 is a, side elevational View of a steam spray gun embodying thefeatures of my invention;

Fig. 2 is a front elevational view of the gun;

Fig. 3 is a sectional view taken substantially along the line 33 of Fig.1;

Fig. 4 is a vertical sectional view taken substantially along the line4-4 of Fig. 2 and showing the internal details of the spray gun;

Figs. 4A and 4B are face and side elevational views of a resilientwasher utilized in the gun;

Fig. 5 is an enlarged sectional view showing the nozzle and adapterfitting illustrated in Fig. 4;

Figs. 6, 7, 8 and 9 are views taken substantially and respectively alongthe lines 6fi, 'I-'I, 88 and 9-9 of Fig. 5;

Figs. 10, 12, 13, 14, 15 and 16 are views taken substantially andrespectively along the lines |Hl, |2|2, |3l3, l4|4, II5, and lB-IB ofFig. 4, Figs. and 13 being on a somewhat larger scale;

Fig. 11 is a sectional view taken along the line llll of Fig. 10;

Fig. 17 is a front elevational view of a steam spray gun embodying analternative form of the present invention;

Fig. 18 is a fragmental side elevational view of the spray gun shown inFig. 17

Fig. 19 is a fragmental vertical sectional view of the nozzle structureembodied in Figs. 1'7 and 18; and

Fig. 2D is a sectional view taken substantially along the line 2il20 ofFig. 18.

For purposes of disclosure, the invention is herein illustrated in Figs.1 to 16 of the drawings as embodied in a steam spray gun 40 having a.main body element 4| that is of the general form utilized in the spraygun of my copending application, Serial No. 734,819, filed March 14,1947, now Patent No. 2,559,407, issued on July 3, 1951, and this bodymember 4| includes a downwardly extending handle portion 42 and aforwardly extending arm 43 at the upper end of the handle 42. The handle42 is of the pistolgrip type and is provided with the usual forwardlyand rearwardly extending finger-engaging lugs 42F and 42R, as is commonpractice in the art, and the forwardly projecting arm 43 has an upwardlyand forwardly extending mounting hook 43H that facilitates suspension ofthe gun from the stationary hook or the like when the gun is not in use.

At the forward end of the arm 43, the gun is provided with an adapterfitting 50 and a spray nozzle 5| that are associated with the arm 43 ina manner that will be described in detail hereinafter, and paint issupplied to the fitting 50 by means including a supply hose 52 while therequired steam is supplied to the fitting 50 by a supply hose 53, aswill hereinafter be described in further detail.

The coating material is, of course, atomized by the action of the steam,as will be described, so as to be discharged from the spray nozzle 5 I,and the flow of the coating material is controlled by a needle valve 55which is associated with an operating plunger 56 and a control triggeror lever 51 in substantially the same manner as the correspondingelements shown in my aforesaid copending application, it being notedthat the trigger or control lever 51' is pivoted at its upper end on thearm 43 by means of a pivot 58, and that this control lever extendsdownwardly along and in spaced relation to the upper forward face of thehandle 42 so that this control lever 51 may be actuated and governed bythe operator in the usual or conventional manner.

Under and in accordance with the present invention, the adapter fitting59 upon which the nozzle 5! is mounted, is arranged to be supported onthe arm 43 of the main body 4| in such a.

manner that the heat supplied to the adapter fitting 50 is nottransmitted back to the handle 42 in any appreciable or objectionabledegree, thereby to assure that the handle 42, as well as the controllever 51, will remain at all times at a temperature sufliciently low toenable the operator to readily handle and manipulate the spray gun.Thus, in accomplishing such mounting of the adapter fitting 50, theforward end of the arm 43 has a downwardly projecting mounting ear 60 atits forward end, this ear 63 being of substantially the same form andarrangement as the corresponding element in my aforesaid copendingapplication. On the forward end of the arm 40, a metallic mounting plate6| is arranged so as to extend over the entire vertical extent of theforward end of the arm 63, as well as the depending ear B0, and thismounting plate BI is substantially rectangular in form, as will beevident in Fig. 14 of the drawings, so as to extend for a substantialdistance on each side of the arm 43. The plate 60 is held in place onthe arm 43 by means including a. screw 62 that extends through the plateBI and into the arm 43 adjacent to the upper edge of the arm 43 andcentrally thereof, as will be evident in Figs. 4, 10 and 12.

The adapter fitting 50 is arranged to be supported in part by the plate6|, as will be described in some detail hereinafter, and this adapterfitting 50 also serves to receive and slidably support the needle valvein substantially the same manner as disclosed in my aforesaid copendingapplication. Thus, the adapter fitting 50 is formed so as to be ofgenerall block-like form with a rearwardly extending nipple 65 thatextends through a bore 66 formed in the ear in axial alignment with thespring plunger assembly 56. The extension of the nipple rearwardlythrough the bore 66 serves as a part of the mounting means forsupporting the adapter fitting on the arm 43, and such support isaugmented by additional means that are connected between the adapterfitting 50 and the upper, outer edge portions of the mounting platefill. The adapter fitting 50 is accordingly provided with spaced,upwardly projecting mounting ears 68 that are formed as parts of anupwardly extended flange 69 that is afforded along the rear, upper edgeof the block-like body of the adapter fitting 50.

The connections between the cars 68 and the plate GI, and theassociation of the nipple 65 with the car 60, are aiTorded under thepresent invention in such a way that transmission of heat by conductionfrom the adapter fitting 50 to the arm 43 is minimized In carrying outthis mounting, the nipple 65 is made of a diameter somewhat smaller thanthe bore 66, and a flanged heat insulating sleeve 19 is put in positionabout the nipple 65 and within the bore 66. The flanged insulatingsleeve 79 has its enlarged flange disposed at one nd against the rearface of the adapter fitting 50, and has its other face or shoulderengaged with the forward face of the mounting plate 6!, thereby to serveas a physical locating element for maintaining the adapter fitting 5B inproper spaced relationship with respect to the mounting plate 6!. Thesleeve 10 terminates at the rear face of the ear 60, and a washer 12,formed of insulating material, is placed on the externally threadedprojecting rear end of the nipple 65 so as to engage the rear surface ofthe ear 60. Just rearwardly of the insulating washer 12, a metallic nut13 is threaded onto the nipple 65 so as to hold the nipple and therelated insulating structure in the proper and desired relationship withrespect to the ar 60.

The nipple 65 serves in the present instance to afford a packing gland14 that is of the same general character as the packing gland describedin my aforesaid copending application, and this packing gland includes apressure spring 15 and a retaining cap 16 of the character disclosed insuch application.

The ears 68 of the adapter fitting 50 are effectually connected to themounting plate Si in th manner shown in detail in Figs. 10, 11, 12 and14. Thus, the mounting plate 6| has apertures 18 formed therein so as tobe disposed opposite apertures 79 formed in the ears 68, as shown inFig. 11, and a spacer sleeve 80 of insulating material is disposedbetween each ear 68 and the plate 6| in alignment with the respectivepaths of apertures. A connecting screw ll is extended rearwardly througheach pair of apertures, so that the heads BIH thereof are spaced fromthe cars 68 by washers B2 of insulating material, and these screwsextend through the respective insulating sleeves 80 and the respectiveopenings 18 so as to project beyond the rear face of the mounting platBl. An insulating washer 83 is placed on the rear end of each screw 8|in abutment with the rear face of the plate BI, and a retaining nut 84made of metal is threaded onto the rear end of each of the screws 81.Thus, the adapter fitting 50 is supported on the arm 43 throughheat-breaker connections so that the heat supplied by the steam that isconveyed through the adapter fitting 50 will not ob ectionably heat upthe handle 42 of the spray gun.

At its forward face, the adapter fitting 50 is provided with a disc-likeportion 85 that has its outer edge threaded to afford a mounting for thespray nozzle 5|, and it should be observed that this disc-like portion85 is centered upon the axis of the nipple 65. In its forward face, thedisc-like portion 35 has a pair of concentrio annular grooves 86 and 81in accordance with the structure and arrangement shown in my aforesaidcopending application, these passages or grooves being utilized inaffording a path for the steam into the nozzle, as will be described.

The nozzle 5|, as herein shown, is afforded as a two-part structurehaving an inner nozzle 90 and an outer nozzle structure 9|. The innernozzle structure 90 is generally in the form of a truncated cone, thelarger end face of which is adapted to seat firmly against the forwardface of the disc-like portion 85, and this larger face has a rearwardlyextending axial nipple 93 that is threaded into a rearwardly extendingbore 94 formed in alignment with the nipple 65 so as to afford aninternal paint-receiving chamber. The paint that is supplied to thisinternal chamber 94 moves forwardly through a bore 95 that extendsforwardly through the nipple 93, and at its forward end, this bor istapered as at 95A into a reduced and forwardly projecting paintdischarge sleeve 96 that affords the discharge opening for the paint aswell as a valve seat for cooperation with the tapered forward end of theneedle valve 55.

The outer nozzle 9| serves to embrace the inner nozzle 90, and is formedas a generally hollow structure having a mounting flange QIF about itsrear edge. The flange 9IF has an internally threaded securing collar 9ICassociated therewith, so that this collar BIC may be threaded onto thethreaded outer dge of the disc-like portion 85, and when this is done, aresilient spring washer 9|W, Figs. 4A and 4B, which is disposed withinthe collar SIC, serves to apply retaining forces for holding the collarQIC in position on the fitting 50. The spring washer 81W also serves tohold the collar SIC on the outer nozzle 9| as described in my aforesaidcopending application.

Within the outer nozzle member 9|, an annular tapered inner surface SITis formed for cooperation or engagement with the outer tapered surfaceof the inner nozzle member 9!! adjacent to the forward end thereof, andjust forwardly of the surface BIT, the outer nozzle has a forward wallBIW which terminates in a central apertur which surrounds the dischargeend 96 of the inner nozzle in spaced relation so that the steam may befed forwardly about the discharge end 96 of the inner nozzle. This steamis supplied to a chamber 10 between the wall 9IW and the forward end ofthe nozzle 90 through a passage IBI extended from the forward end of thenozzle 90 and rearwardly in a location such that it will meet theannular passage 81 to which discharge steam is supplied, as will bedescribed hereinafter.

The nozzle 9| also embodies wing jets I04 that have the passages thereofconnected to an annular groove I05 formed in the internal surface of thenozzle member 9|. While different arrangements of control orifices maybe afforded in the wing jets I04 and in other portions of the outernozzle member 9|, it will be noted that in the present instance a pairof angularly directed control orifices [94.] are formed in therespective wing jets Hi4, and a plurality of supplemental control jetsIMH are provided in the wall 9IW in a symmetrical pattern around thecentral discharge orifice and sloping slightly toward the axis of thespray nozzle. Steam is supplied to the annular passage I05 from theouter annular groove 86 of the adapter fitting 50. Thus, it will benoted that near its rear edge the outer nozzle member 9| has a taperedannular surface II" that engages the outer tapered surface of the innermember 90, and this engagement is for centering and aligning purposes.However, this surface I01 has a number of slots I08, Figs. 4, 5 and 6,formed therein that serve to afford communication between the outerannular groove and the annular groove I05, thereby to supply steam tothe wing jets I04. It might be observed that while the outer surface ofthe inner nozzle member 90 is generally conical in form, flattenednutlike faces I09 are afforded on opposite sides thereof and in thespace between the points of engagement of the surfaces SIT and H11, asshown in Fig. 7, so that this inner nozzle member 90 may be engaged witha wrench to screw the nipple 93 thereof into or out of the threaded bore94.

As shown in Fig. 4, the rear end of the needle valve 55 is operativelyconnected with the spring unit 56, and this spring unit comprises aninner sleeve H0 that has a flange IIDF at its forward end. and thethreaded rear end of the needle valve 55 is extended through a centralopening in this flange. A pair of nuts HI are threaded on to the alve 55within the sleeve H9. The sleeve H0 is in turn mounted within a sleeveH2 which is threaded into a suitable bore formed in the handle 42 andaligned with the bore 66 of the ear 60. The sleeve III! has a flangeIIIJG at its rear end, and this flange is disposed within a cap memberII3 that is threaded onto the projecting rear end of the sleeve I I2.The sleeve II3 affords a shoulder II3S against which the flange IIllGmay engage when it is moved in a forward direction, thereby to limit theforward movement of the sleeve Il0. A closure head H4 is removablythreaded into the end of the cap or sleeve I I3, and a spring I I5disposed within the sleeve III) acts between the head H4 and the nuts III to urge the sleeve H and the associated needle valve 55 in a forwarddirection. The needle valve 55 is thus normally closed and rearwardopening forces are applied to the needle valve by engagement of anabutment 51A on the control lever 51 with the forward end of the sleeve56.

While the spring plunger arrangement 55 and the nozzle structure havebeen described in some detail hereinbefore, it is to be observed thatthese elements may take different conventional forms insofar as thepresent invention may be concerned.

The supply of coating material is conducted to the chamber 94 in theadapter fitting 50 through means including the supply hose 52, and thissupply hose 52 is arranged with a conventional hose coupling member I I8at its upper end. The coupling member H8 is arranged to be threaded ontothe lower end of a double nipple IIO, the upper end of which is threadedinto a vertical bore I that is extended upwardly into the lower face ofthe adapter fitting 50 adjacent to the lefthand edge thereof as viewedin Figs. 2 and 10, thus to communicate with a transverse passage I22that extends laterally into the chamber 94.

Similarly, the steam is supplied to the adapter fitting 50 through thesupply hose 53 which has a hose connector fitting I23 at its upper end,and this fitting I23 is threaded onto the lower end of a double nippleI24, the upper end of which is threaded into a vertical bore I25 that isextended upwardly into the lower face of the adapter fitting 50 adjacentthe other edge thereof. Steam that is thus supplied to the bore I25 isconducted to the annular groove 86, as well as to the annular groove 81,thereby to supply steam for the wing jets I04 and for the aspiration ofthe coating material through the discharge end 96 of the inner nozzle.Thus, a first bore I2! is extended in a forward and somewhat angulardirection from the bore I25 so as to extend to the inner annular groove81, as will be evident in Figs. 10, l1 and 13, and this affords aconstant steam supply to the groove 81.

The other connection is afforded, of course, to supply steam to the wingjets I34, and since the rate of motive fluid discharge from these wingjets serves in a known manner to control the spray pattern, theconnection with the groove 85 is arranged so that the effective area maybe regulated by settable valve means. Thus, in affording suchconnection, a bore I23 is extended rearwardly and in a somewhat angulardirection into the fitting 50 from the bottom of the channel 86, andnear its rear end this bore I28 intersects with a vertical bore I29 thatis extended upwardly from the upper end of the bore I25. This affords aconstant steam supply connection between the bore I25 and the wing jets,and valve means for adjusting the effective area of this passage areprovided in a laterally and horizontally extending bore I30 that opensthrough the right-hand side of the adapter fitting 50, as viewed in Fig.13. This bore I30 intersects with the bore I28, and in the portion ofthe bore I30 that is adjacent to the bore I28, screw threads I308 areprovided for cooperation with complemental threads formed on a valvemember I3I. This valve member I3I has its left-hand end, as viewed inFig. 13, formed in a rounded shape so that it may scat tightly againstthe lefthand side of the bore I28, as will be evident in Fig. 13. Justto the right of the screw threads I30S, the bore is enlarged as at I30Eto receive compressible packing material I32. This packing material isadapted to be compressed by a packing sleeve I33 that is threaded intothe righthand end of the bore I30E, as will be evident in Fig. 13. Theouter end of the valve I3I projects beyond the end of the packing sleeveI33, and has a transverse kerf I33K formed therein so that the valvemember I3I may be readily adjusted.

It will be observed, particularly in Fig. 13 of the drawings, that theend of the valve member I3I is disposed over one of the laterallyextending ends of the adapter fitting 50, and it should be observed thatthese ends extend outwardly from the central line of the bore 34 in anamount such that parallel end surfaces 5UP on the adapter fitting 50constitute pads that may be engaged for clamping the adapter fitting 50in a vise. This enables the inner and outer nozzle members and BI to bereadily removed, and also facilitates the attachment of other screwthreaded parts such as the nipples H9 and I24 to the fitting 50.

The hoses 52 and 53 are, under the present invention, associated withthe other elements of the gun in such a way as to afford an unusuallyfine balance for the gun and the attached hose structures, and this isattained by afiording means on the gun for holding adjacent lowerportions of the hoses in a predetermined relationship with respect tothe gun. Thus, as will be evident in Figs. 1, 2 and 3, a locating andsupporting bracket I35 is formed from sheet metal and is attached bymeans such as screws I36 to the lower end of the handle 42, and thebracket I35 extends forwardly and downwardly from the lower end of thehandle 42. At its forward end, the bracket 52 has a pair of oppositelycurved retaining hooks I31 and I38 that are of such a size that thehoses 52 and 53 may be put in position within the respective hooks. Whenthis is done, the two hoses curve rearwardly as indicated at 52C and 53Cin Fig. 1 of the drawings, and this serves to so locate the lowerportions of the hoses with respect to the gun that proper balance of thegun is attained.

In the use of the gun, the operator must necessarily locate one or moreof his fingers about the forward surfaces of the lower end of thecontrol lever 51, and this, of course, places the operators finger orfingers relatively close to the steam hose 53 and its connectingfittings. While many operators do not find this to be objectionable, Ihave found that all danger that might otherwise arise from thissituation may be eliminated through the provision of a downwardlydepending protective shield I40 in the form of a relatively thininsulating plate. This insulating plate I40 may be made from a materialsuch as vulcanized fiber and may be secured at its upper end to theforward face of the mounting plate BI by putting the same in positionprior to the mounting of the screw 62, the screws 8|, and the otherconnecting elements therethrough. The plate I40 is extended down to alevel somewhat below the lower end of the control lever 51.

In Figs. 1'7 to 20 of the drawings, an alternative embodiment of theinvention is afforded which incorporates two additional features thatare of marked advantage in steam spraying of surface coating materials.Thus, in this alternative form of the invention, a spray gun 240 isprovided which in most of its structural characteristics is similar tothe embodiment here inbefore described, and where there iscorrespondence of form and function, the same reference characters areutilized for corresponding structural elements. It will be noted in thisembodiment of the invention that the hose connections to the adapterfittting 5B are considerably modified, and in accomplishing this, meansare afforded for pre-heating the surface coating material before itreaches the spray nozzle 5|. Thus, a pre-heating unit MI is afforded,and this pre-heating unit comprises a pair of relatively small metalpipes 242 and 243 that are connected to the bores I20 and I25 of theadapter unit 50, in place of the nipples H9 and I24, this beingaccomplished by conventional connector devices 244 and 245. Just belowthe points of connection with the adapter fitting 50, the pipes 242 and243 are bent toward each other so as to be disposed for a substantialdistance in a side by side relationship, as will be evident in Fig. 20of the drawings. The two pipes are then bent outwardly at their lowerends into a separated relationship, and connector nipples 24B and 241are secured on the respective lower ends thereof so that the connectorfittings H8 and I23 of the two hoses 52 and 53 may be connected thereto.The length of the pipes 242 and 243 is such that the two connectornipples 246 and 241 are disposed in a slightly spaced relationshipbeneath the lower end of the handle 42, and a bracket 248 is secured byscrews 249 to the lower end of the handle so as to project forwardly anddown wardly from the handle for association with the pipes 242 and 243.

Under the present invention, the heat transfer relationship between theside by side portions of the pipes 242 and 243 is rendered moreefficient by the provision of an enclosing sleeve 250 formed from aninsulating material and extending along the two pipes 242 and 243throughout the portions thereof that are located in side by siderelationship. Clamping collars 25I and 252 are provided about the upperand lower ends, respectively, of the insulating sleeve 25!! so as tohold the same securely in position about the pipes. The bracket 248 isconnected to the lower portion of the sleeve 250 just above the clampingcollar 252, and this is accomplished by means of another clamping collar253 that is secured as by welding at 254 to the lower, forward end ofthe bracket 248. It will be evident that with this pre-heating unit 24I,the balance of the spray gun is maintained while at the same timeassuring that when the coat ing material reaches the spray nozzle, suchcoating material will be in a pre-heated condition so as to therebyincrease the efiiciency of operation of the spray gun.

In the use of a steam spray gun, it is important that the nozzleportions of the gun be maintained at a relatively high workingtemperature at all times, even though the spraying operation may beinterrupted, and in order to accomplish this, the steam is allowed toflow through the gun at all times, and the control of the sprayingoperation is attained solely through the opening and closing of theneedle valve 55. Because of this constant flow of steam, there ma be atendency under some circumstances for the steam to condense upon partsof the gun, and this is particularly true in the event that the screwthreaded connections, such as the connector afforded by the collar BlC,are not absolutely tight against the flow of steam under pressure. Inthe embodiment of the invention illustrated in Figs. 17 to 29, means areafforded for disposing of any such condensate without impairment of theoperation of the spray gun. This is accomplished through the provisionof a relativel large drip plate 26!] that is disc-like in form and whichhas a central sleeve-like flange surrounding the outer nozzle 9| justforwardly of the connecting element BIG and fixed thereto as by brazingat 260B. This disc-like member 280 extends radially outwardly and thenassumes a somewhat conical form so as to slope in a rearward direction,and thus a lower discharge or dripping edge 260E, Fig. 19, is affordedso that any condensate that may gather upon the parts of the nozzle maydrip downwardly off of such edge. It will be noted in this regard thatthe edge 260E is located a considerable distance rearwardly and aconsiderable distance downwardly from the discharge end of the nozzle sothat the natural air flow past the disc will be at a rate or speed thatis sufiiciently low to avoid drawing the dripping condensate into thepaint spray.

From the foregoing description, it will be apparent that the presentinvention enables'a steam spray gun to be so constructed that the handleof the gun may be readily held and manipulated by the operator, and itwill also be apparent that this is accomplished in such a way that thedesired balance of the spray gun is attained and addition of excessiveweight to the spray gun is avoided. It will also be evident that thepresent invention provides for pre-heating of the surface coatingmaterial, thereby to render the spraying operation more effective.Moreover, it will be observed that under the present invention, anycondensate that may form on the spray head is disposed of in such amanner that it is not drawn into the paint spray, thereby to assure theproduction of high quality surface coating.

Thus, while I have illustrated and described the preferred embodiment ofmy invention, it is to be understood that this is capable of variationand modification, and I therefore do not wish to be limited to theprecise details set forth, but desire to avail myself of such changesand alterations as fall within the purview of the following claims.

I claim:

1. In a steam spray gun, a main body element affording a pistol-griphandle with a mounting arm projecting forwardly from its upper end andhaving a movable control lever projecting downwardly along and in spacedrelation to the forward edge of said handle, a spray head havingcooperating passages for coating material and for steam to be employedas the motive fluid, an adapter fitting element on the forward face ofwhich said spray head is mounted, said fitting element havingindependent passages formed therein and operatively connected to thesteam and coating material passages of said spray head, heat-breakingconnecting means supporting said adapter fitting element on the forwardend of said arm and comprising at least one screw threaded elementacting between said fittin element and said body element and a pluralityof rigid heat insulating members clamped in position between saidfitting element and said body and screw threaded element, and a needlevalve mounted in said fitting element for controlling discharge ofcoating material from said spray head and operatively connected to saidcontrol lever for actuation thereby.

2. In a steam spray gun, a main body including a handle and a controllever, a spray head, an adapter fitting, means affording interconnectingcoating material passages in said fitting and said head through whichcoating material supplied to said fitting may be fed, means affordinginterconnecting steam passages in said fitting and said head throughwhich steam supplied to said fitting may flow as a motive fluid toeffect heating, atomization and discharge of the coating fluid as aspray, a needle valve mounted in said fitting and connected to saidcontrol lever for governing such discharge of coating material, andrigid means made of heat insulating material and disposed between saidfitting and said body, screw threaded clamping means acting between saidbody and said fitting and extending through said rigid means tocooperate with said rigid means to support said fitting on said body ina heat-breaking relationship so as to thereby effect substantial thermalisolation of said fitting and spray head with respect to said main body.

3. In a steam spray gun, a main body including a handle and a controllever, a spray head,

an adapter fitting, means affording interconnecting coating materialpassages in said fitting and said head through which coating materialsupplied to said fitting may be fed, means affording interconnectingsteam passages in said fitting and said head through which steamsupplied to said fitting may flow as a motive fiuid to effect heating,atomization and discharge of the coating fluid as a spray, a steamcontrol valve mounted on said fitting and effective to control the flowof steam therethrough, a needle valve mounted in said fitting andconnected to said control lever for governing such discharge of coatingmaterial, and spacer means made of heat insulating material and disposedbetween said body and said fitting and screw threaded clamping meansconnected between said body and said fitting and extended through saidspacer means to support said fitting on said body in a heatbreakingrelationship so as to thereby effect substantial thermal isolation ofsaid fitting and spray head with respect to said main body.

4. In a steam spray gun, a main body affording a pistol-grip handle witha mounting arm projecting forwardly from its upper end and having amovable control lever projecting downwardly along and in spaced relationto the forward edge of said handle. a spray head having cooperatingpassages for coating material and for steam to be employed as the motivefluid, an adapter fitting on the forward face of which said spray headis mounted, said fitting having independent passages formed therein andoperatively connected to the steam and coating material passages of saidspray head, means comprising a plurality of rigid heat-breakerconnections supporting said adapter fitting on the forward end of saidarm, a needle valve mounted in said fitting for controlling discharge ofcoating material from said spray head and operatively connected to saidcontrol lever for actuation thereby, steam and coating material supplyconduits connected to the lower face of said fitting and extendedrearwardly and downwardly therefrom, and a positioning bracket connectedto the lower end of said handle and to said conduits to support saidconduits in a balanced relation to said gun.

5. In a steam spray gun, a main body affording a pistol-grip handle witha mounting arm projecting forwardly from its upper end and having amovable control lever projecting downwardly along and in spaced relationto the forward edge of said handle, a spray head having cooperatingpassages for coating material and for steam to be employed as the motivefluid, an adapter fitting on the forward face of which said spray headis mounted, said fitting having independent passages formed therein andoperatively connected to the steam and coating material passages of saidspray head, means comprising a plurality of rigid heat-breakerconnections supporting said adapter fitting on the forward end of saidarm, a needle valve mounted in said fitting for controlling discharge ofcoating material from said spray head and operatively connected to saidcontrol lever for actuation thereby, steam and coating material supplyconduits connected to the lower face of said fitting and extendedrearwardly and downwardly therefrom, a positioning bracket connected tothe lower end of said handle and to said conduits to support saidconduits in a balanced relation to said gun, and means thermallyassociating said conduit in a heat-transfer relationship between saidbracket and said fitting for rendering the steam effective to preheatthe coating material as it moves toward said fitting.

6. In a steam spray gun, a, main body affording a pistol-grip handlewith a mounting arm projecting forwardly from its upper end and having amovable control lever projecting downwardly along and in spaced relationto the forward edge of said handle, a spray head having cooperatingpassages for coating material and for steam to be employed as the motivefiuid, an adapter fitting on the forward face of which said spray headis mounted, said fitting having independent passages formed therein andoperatively connected to the steam and coating material passages of saidspray head, means comprising a plurality of rigid heat-breakerconnections supporting said adapter fitting on the forward end of saidarm, a needle valve mounted in said fitting for controlling discharge ofcoating material from said spray head and operatively connected to saidcontrol lever for actuation thereby, a, pair of tubular membersconnected respectively to said steam and coating material passages ofsaid fitting and extending downwardly and rearwardly therefrom andterminating in lower ends disposed somewhat below the lower end of saidhandle, hose connector fittings on the lower ends of said tubularmembers, a bracket extended between said handle and said tubular membersfor supporting the lower ends of said tubular members in a balancedrelation with respect to the gun, portions of said tubular members beingdisposed in a side-by-side relation, and a heat insulating sleevesurrounding said portions of said members to promote heat transfertherebetween for preheating the coating material.

7. In a steam spray gun, a main body affording a pistol-grip handle witha mounting arm projecting forwardly from its upper end and having amovable control lever projecting downward- 1y along and in spacedrelation to the forward edge of said handle, a spray head havingcooperating passages for coating material and for steam to be employedas the motive fiuid, an adapter fitting on the forward face of whichsaid spray head is mounted, said fitting having independent passagesformed therein and operatively connected to the steam and coatingmaterial pas sages of said spray head, a metallic mounting plate securedto the forward end of said arm in a vertical and transverse relation, aplurality of heat-insulating spacer sleeves disposed between saidmounting plate and the rear face of said fitting, screw-threadedsecuring means extended through said sleeves and clamping said fittingand said plate against opposite end surfaces of said sleeves, and aneedle valve extended through one of said sleeves for controlling thedischarge of coating fluid and operatively connected to said controllever.

8. In a steam spray gun, a main body affording a pistol-grip handle witha mounting arm projecting forwardly from its upper end and having amovable control lever projecting downwardly along and in spaced relationto the forward edge of said handle, a spray head having cooperatingpassages for coating material and for steam to be employed as the motivefluid, an adapter fitting on the forward face of which said spray headis mounted, said fitting having independent passages formed therein andoperatively connected to the steam and coating material passages of saidspray head, means comprising a plurality of rigid heat-breakerconnections supporting said adapter fitting on the forward end of saidarm, a needle valve mounted in said fitting for controlling discharge ofcoating material from said spray head and operatively connected to saidcontrol lever for actuation thereby, and a shield plate of heatinsulating material suspended from the forward end of said arm anddepending for a substantial distance therefrom and in forwardly spacedrelation with respect to said control lever for protecting the fingersof the operator.

9. In a steam spray gun, a main body affording a pistol-grip handle witha mounting arm element projecting forwardly from its upper end andhaving a movable control lever projecting downwardly along and in spacedrelation to the forward edge of said handle, a spray head havingcooperating passages for coating material and for steam to be employedas the motive fiuid, an adapter fitting element on the forward face ofwhich said spray head is mounted, said fitting element havingindependent passages formed therein and operatively connected to thesteam and coating material passages of said spray head, means supportingsaid fittin element on the forward end of said mounting arm elementcomprising rigid heat insulating means disposed as a spacing meansbetween at least certain of the opposed surfaces of said elements,headed screw threaded fastening means extended through one of saidelements and said heat insulating means and anchored to the other ofsaid elements to hold said elements together and in clamped relation tosaid heat insulating means, further rigid heat insulating meanssurrounding said screw thread means and actin as heat insulation betweensaid one element and said screw threaded means, and a needle valvemounted in said fitting element for controlling discharge of coatingmaterial from said spray 14 head and operatively connected to saidcontrol lever for actuation thereby.

10. In a steam spray gun, a main body affording a pistol-grip handlewith a mounting arm element projecting forwardly from its upper end andhaving a movable control lever projecting downwardly along and in spacedrelation to the forward edge of said handle, a spray head havll'lgcooperating passages for coating material and for steam to be employedas the motive fluid, an adapter fitting element on the forward face ofwhich said spray head is mounted, said fitting element havingindependent passages formed therein and operatively connected to thesteam and coating material passages of said spray head, means supportingsaid fitting element on the forward end of said mounting arm elementcomprising rigid heat insulating means disposed as a spacing meansbetween at least certain of the opposed surfaces of said elements,headed screw threaded fastening means extended through one of saidelements and said heat insulating means and anchored to the other ofsaid elements to hold said elements to ether and in clamped relation tosaid heat insulating means, further rigid heat insulating meanssurrounding said screw thread means and acting as heat insulationbetween said one element and said screw threaded means, a rearwardlyprojecting nipple formed on said fitting element and affording a packinggland for said needle valve, and means including a rigid heat insulatingsleeve surrounding said nipple and engaging said mounting arm element toaccurately locate said nipple relative to said main body.

11. In a steam spray gun, a main body element including a handle and acontrol lever, a spray head, an adapter fitting element, means affordinginterconnecting coating material pas sages in said fitting element andsaid head through which coating material supplied to said fittingelement may be fed, means affording intel-connecting steam passages insaid fitting through which steam may flow as a motive fluid to effectheating, atomization and discharge of the coating fluid as a spray, asteam supply connection extended from said fitting element, a needlevalve mounted in said fitting element and connected to said controllever for governing such discharge of coating material, and rigid meansincluding rigid spacer means made of heat insulating material disposedbetween said fitting and body elements and screw threaded fastener meansconnected between said fitting and body lements, and annular rigidspacer members surrounding said fastener means and spacing said fastenermeans from one of said elements, to thereby support said fitting elementon said body element in a heat-breaking relationship and effectsubstantial thermal isolation of said fitting element and spray headwith respect to said main body element.

12. In a steam spray gun, a main body affording a pistol-grip handlewith a mounting arm element projecting forwardly from its upper end andhaving a movable control lever element projecting downwardly along andin spaced relation to the forward edge of said handle, a spray headhaving cooperating passages for coating material and for steam to beemployed as the motive fluid, an adapter fitting on the forward face ofwhich said spray head is mounted, said fitting having independentpassages formed therein and operatively connected to the steam andcoating material passages of said spray head, a steam connectionextending from the lower side of said fitting, means affording rigidheat-breaker connections supporting said adapter fitting rigidly on theforward end of said arm element, a needle valve mounted in said fittingfor controlling discharge of coating material from said spray head andoperatively connected to said control lever for actuation thereby, and ashield of heat insulating material suspended from one of said elementsin position to protect the fingers of the operator from the heat of saidsteam connection.

WILLIAM P. DALRYMPLE.

- 16 REFERENCES CITED The following references are of record in the fileof this patent:

UNITED STATES PATENTS Number Name Date 1,773,582 Jackson Aug. 19, 19301,934,826 Shepherd Nov. 14, 1933 2,129,778 Middleton Sept. 13, 19382,265,209 Thompson Dec. 9, 1941 2,282,214 Albertson May 5, 19422,378,184 Carlson June 11, 1945 2,411,181 Altorfer Nov. 19, 19462,526,405 Peeps Oct. 1'7, 1950 2,559,407 Dalrymple July 3, 1951 Noticeof Adverse Decision in Interference In Interference No. 87,792 involvingPatent No. 2,621,970, W. P. Dalrymple, Spray gun, final judgment adverseto the patentee was rendered April 10, 1957, as to claims 2 and 3.

[Ojfioial Gazette May W, 1957.]

Disclaimer 2,62l,970.-Wz'lliam P. Dalrymple Rochester, N. Y. SPRAY Gmr.Patent dated Dec. 16, 1952. Disciaimer filed Apr. 24, 1957, by theassignee, Egener Corporation. Hereby enters this disclaimer to claims 1and 2 of said patent.

[Olficz'al Gazette May #38, 1.957.]

